Explorer 12 with curved cab from China. Bigger wheels are mounted on small ones. http://projectswordtoys.blogspot.fr/2013/06/exploring-explorers.html

Explorer 12. These all terrain toys were made by Super Toys Inc, California, and after by Galgo, Argentina and in 1994 in China. http://explorer12s.blogspot.co.uk/search?updated-min=2009-01-01T00:00:00Z&updated-max=2010-01-01T00:00:00Z&max-results=11